The most recent episode of AMC’s zombie show The Walking Dead was notable for the unexpected appearance by a legendary, terrifying beast whose regular diet probably includes recently slain, uncooked woodland creatures .

I refer, of course, not to the mythical, sheep-devouring chupacabra, after which the show was named, but actor Michael Rooker’s even more frightening, racist redneck Merle Dixon, who appeared in a vision to encourage and berate his brother, Norman Reedus’ injured Daryl.

Below, Walking Dead writer and executive producer Robert Kirkman – who also pens the long-running Walking Dead comic – talks about the much awaited return of Merle, the revelation that Scott Wilson’s Hershel is keeping something rather more dangerous than bales of hay in his barn, and the strong possibility that Jon Bernthal’s tortured Shane is “an a–hole.”

ENTERTAINMENT WEEKLY: Michael Rooker!
ROBERT KIRKMAN: Exactly, right? It’s unfortunate that it was just a vision, a hallucination of some sort. But having him back in the show was an absolute delight. Hopefully it will happen again at some point soon.

I love the way you say “hopefully” as if this has nothing to do with you.
[Laughs] I’m trying to be coy! My favorite thing was that we hadn’t ever seen those characters interact. I guess we still technically haven’t. But this is the first time Rooker and Reedus have been in a scene together, which is really cool.

Is it fun thinking up new ways for Daryl to be a bada–?
It really is. It’s nice seeing Daryl out there on his own. We established early on that he is the survivalist of the group and also it’s interesting that this guy who does seem to be a bit of prickly pear is the one that is throwing himself gung-ho into this mission of searching for Sofia. So it is nice to see a little bit of a soft side to him. But at the same time, you’re watching him cut zombies’ ears off and making a necklace out of them, which is a little bizarre.

Bizarre, yes. But also, I couldn’t help feeling, unhygienic. As my father used to say, if you’re going to make a necklace out of ears, make sure they’re fresh.
[Laughs] Did he get that advice from Michael Rooker?

What book was being maligned by Dale? I couldn’t see the cover.
I have no idea! I wish I knew. I don’t think it was written to be a specific book.

I bet it wasn’t Rise of the Governor (the Kirkman-cowritten Walking Dead prequel novel), which I believe is now available at all good book stores.
[Laughs] It probably isRise of the Governor. Who knows?

Presumably Hershel was just hoping they wouldn’t find out?
I think that was his futile hope, that he would be able to save their kid and send them along their way without them finding out. I mean, if you go back and watch the episodes, any time there’s been any kind of mention of killing zombies there has been some kind of reaction from people in the Hershel camp. It should be fun to go back and witness that stuff. Hershel has a fundamental difference of opinion on what a zombie is and what should be done with them and that’s going to lead to quite a bit of conflict.

Finally, going back a couple of episodes, a lot of ew.com commenters wondered about Shane’s shooting Otis in the leg rather than the head. Is that evidence of Shane being crazy? Or would a wounded but live Otis occupy more zombies than a dead one?
It was the idea that if he was screaming and moving about he would draw more walkers to him while he was being devoured. And Shane is an a–hole. [Laughs]